Photographic element with colloid layer containing color former and nonionic wettingagent



Patented Dec. 4, 1 951 UNIT-ED STATE s PATENT OFFICE PHOTOGRAPHIC ELEMENT wrrn COLLOID LAYER CONTAINING ooLoE FORMER AND NONIONIC WETTING AGENT Andrew Bradshaw'Jennings, Edgebrook, and Otis -Willard Murray, Rumson Park, N. J., assignors Y to E. I. du Pont' de Nemours-& Company, Wilmington, Del., a corporation of Delaware No Drawing.

- This, invention relates to color photography. More; particularly, it relates to color-forming silver halide emulsions and emulsion layers containing non-ionic wetting agents. It also relates tophotographic elements containing such emulsion layers. v 4

It has been proposed to add various wetting agents of the ionic type to photographic silver halide emulsions with high molecular weight color formers in order tofacilitatedispersion of the latter. The wetting agents-so proposed have the objection that they leave a colored stain in theemulsion layers after development and removal of the silver images andsilver salts. This stain results in a multicolor picture which has improper color values and is not an; accurate reproduction. v p

An object of the present invention is to improve the chromogenio development of silver halide images. i A further object is to eliminate .the stain in prior art procedures 'utiliz ing wetting agents. Another object is to providephoto graphic emulsion layers which canbecolor de veloped and washedwithout producing objectionable color, stain. Still other objects will be apparent irom the following description of the invent on- I f It has been found that the addition of- 110119 ionic wetting. agents to photographic. silver halide emulsion layers 'priorto. development thereof is advantageous in the colordevelopment thereof. It'isespecialy true of such development when high molecular weight or non-difiu sing' color formers or polymeric color formers are present inthe emulsion layers.- Such agents'are preferablyadded to the photographic silver halide emulsionsprior to 'the'addition'of the color for: mers thereto because they assist in the dispersion of the color formers in such emulsions.

Various types of non-ionic wetting'agents are known.-. In'general, they are free from sulfonic acid "andcarboxylic acid groups and uaterna y nitrogen salt groups and contain a plurality of oxygen atoms. "A class of especially usefulproducts have a structure which is exemplified by the following hexitans and hexidederivative formulae i Application'November 23, 1946, Serial No. 711,836

g *acl ims. (01. -7)

able commercially. They can be prepared in various ways; for example, by the removal of water from glycols and by the reaction of oxides with glycols. The reactions are generally carried out until the products have a molecular weight or an average molecular weight in excess of 400.

Ethylene'oxide, propylene oxide-1,2, and -l,3 and butylene' oxides-1,2 can be used in the preparation of the products and they may be reacted with ethylene glycol, diethylene glycol. Their preparation is described in The Chemistry of Synthetic Resins, pages 990-994 published by Rheinhold Publishing Corp. (1935). v

Preferred compounds of this type may be represented by the formula where n is 7 to 200 or more. Compounds having such a formula include nonaethylene glycol, decaethylene glycol, dodecaethylene glycol and higher homologues containing from 9 to 200 CH2CH2O groups. The lower members of the class are viscous liquids to semi-solids and: solids, at 20 C., which are somewhat hygroscopic up to a molecular weight in excess of 1500. The higher homologues are waxy solids and as their molecular weight increases to 4000 they become non-hygroscopic in character. The lower members of the series are easily soluble in water, the solubility becoming less as the molecular weights of the compound increase. In general, the higher members or the series cannot be too easily isolated. as single chemical entities. Instead, the

weight. Since a difference of one or two ethylene.

oxide links in polymers of considerable chain length has a negligible effect ontheir physical and chemical properties, such mixtures ca rl be readily employed in the present inventioi-n For the purposes of this invention, it is. sufiieient to know the average molecular 'vweightbfthe ma:

terial to be used and the fact that it may in an" weights does The lower alkyl ethers and carboxylic'a'c'id esters of the aforesaid polyglycols are also usefuL;

Among such ethers and esters are the monoand di-methyl and monoand di-ethyl ethers and the monoand di-acetates, formates, and propionates.

Still other useful compounds are disclosed in Meincke United States Patent 2,341,846 which are free from free sulfonic and carboxylic acid or their salt groups. Yet others are disclosed in Swan United States Patent 2,240, 17 2.

The compounds are preferably admixed with the silver halide colloid emulsions prior to the addition ot the color formers. This may be accomplished by means or water or water-solvent mixtures, e. g., methyl alcohol, ethyl alcohol,-and acetone, containing the non-ionic wetting agents. The color formers can beadded fromthe same solution or separately. After addition of the color former and wetting agent, the solution is brought to a proper viscosity for coating". The non-ionic wetting agents may be used over a wide range of proportions. n practical range is 0.1 gram to 2.0 grams per liter of'colloid silver halide emulsion; V V a H Various types of hydrotropic wetting agents may be used in conjunction with the non-ionic wetting agents if desired. They eliminate or remove any stain producedby ionic wettingag-ents upon an adequate washing of the color developed elements. I a

The non-ionic wetting agents aid} in coating of color-forming photographic colloid silver halide emulsion layers and prevent coating streaks, repellent spots and bubble formation. In addition, they permit satisfactory rewetting of the dried layers.- A I The invention will be further illustrated by the following examples.

Example I To 250 grams of a negative type, flowable, gelatino -silver iodobromide emulsion is addedpne gram of 4,4-methylene-bis-(l-phenyl-S -methyl 5-pyrazolone) Two cublc centimeters of a aqueous solution of a mannitan monolaurate containing 2 to 3 polyoxyethylene chains of 8- or more carbon atoms is added. The resulting emulsion is coated onto a cellulose acetate film base and dried. The film element isexposed to forman image record and then developed in a solution of the following composition:

N p diethylaminoariiline hydrochloride grams. 8.0

A similar emulsion is prepared by substituting sodium dodecylsulfate for the mannitan derivative and coated and the resulting element exposed and processed inlike manner. The two developed elements are then bleached in potassium ferrieyanine' and fixed irisodiu'in' thiosulfate. In each case the highlight density was measured to determine the amount of stain present. The latter el'enjienthas' 50'% lrnore stain when measured by a densitoxiieter than the former.

There was no evidence or diirerences in black and white fo onthe two films.

Similar results are obtained by adding 12 cc. of 5% saponjin' solution to the emulsions prior to coating.

.. Example II licellulose acetate film base is coated with an 8% aqueous gelatin solution containing one gram of 4,4'-bis- (1-naphthol-2-sulfamidophenyl) ether, l0 cc. of 5% aqueous saponin solution, and 1 cc. of the marinitan derivative of Example- I' 'per cc. ofgelatin' solution to form a thin, color-yielding substratum. A- gel'atino=siiver' iodobromide emaision cont n ing of 5%- sa 'dnin solution and '1 %ef the same mannitan moneiaurate derivative per 100 cc. of wet emulsion is coated onto said substratum." a a A- similar element is made" by substituting" for the non iojiiic'we'tting' agent siiiiilai amounts of sodium dcdecyi sulfate.

The twdeleinents j-i'ist d'escrioedare exposed to an object and clevelopedbleached, fixed, and washed as Example I i The first element is practically free from color stain, whereas the latter has a significant color stain.

The elements are not limited to the particular film elements described above. Thus single and multilayer elements on various types of supports, e; g pa er, metal, superpolyiiieis, e. g'., nylon polystyrene, polymerized methyl rhethac'rylate', polyvinyl chloride;- cellulose nitrate, cellufose' acetate' propionate', ce uiose acetate utyrate, etc. may' be made. Mu il'ayer elements containing, for example, c ifierent color formersand the same or different nofi 'ionic' wettmg" agent's can-be made like manner by coating the coloi -yiel di l ig emulsions onto the support or a coated layer super osed thereon.-

' Inpla'ce' of the speeificcolor formers described in the examples, there may be substituted other such materials. Among the useful onesare those described United States Patents 2,294,909, 2,368,3Q2, 2,395,484, 2,397,86g,2-,-397,-865,- 2,397,867, 2,219,426., 2,299,64land- 2,283,276; g

. In place ofthe saponin of the above examples, there may be substituted various other hydrotr'opic agents. Suitable additional ones include alkali metal salts of alkylated naphthalene sulionic acids, alkali metal salts of long" chain alkyl sulfates and alkyl sulfonat'es. Still other'hydrotropic agents are described in Uiiman Encyclopf fedie' derfIechnischen Chemie', 2nd edition, vol. I x, page e08. The agents may be; used over; a rainy wide range. For example. they may be 'd n the water permeable layers, both or" the lil'i -sen'. siti ve afid lightihsensitive type, an amount fr 'dm 0.05 w 1% or more, based on the solids in solution.

An advantage of the invention is that it pro vides a simple and economical method of removing color stain from photographic elements. A further advantage is that the agents improve the rewetting characteristics of a water-permeable colloid layer resulting in a uniformity of results.

As many widely-different embodiments of this invention can be made without departing from the spirit and scope thereof, it is to bev underwhere X is a member of the group consisting of OH and NHR, where R is a member of the group consisting of H and aliphatic hydrocarbon radicals, said color former being capable of forming a dye taken from the group consisting of quinoneimine and azomethine dyes and a nonionic wetting agent having a molecular'weight of at least 400, and a plurality of oxyalkylene groups in a chain of atoms, said agent being free from sulfonic and carboxylic acid and quaternary nitrogen salt groups.

2. A photographic element bearing a light:- sensitive silver halide stratum and at least one gelatin layer containing a color former containing as an active color-coupling group a structure of the formula x =t t=tn where X is a member of the group consisting of OH and NHR, where R is a member of the group consisting of H and aliphatic hydrocarbon radicals, said color former being capable of forming a dye taken from the group consisting of quinoneimine and azomethine dyes and a nonionic wetting agent having a molecular weight of at least 400, and a'plurality of oxyalkylene groups in a chain of atoms, said agent being free from sulfonic and carboxylic acid and quaternary nitrogen salt groups.

3. A photographic element bearing a lightsensitive silver halide stratum and at least one water-permeable colloid layer containing a color former containing as an active color-coupling group a structure of the formula where X is a member of the group consisting of OH and rNHR, where R is a member of the group consisting of H and aliphatic hydrocarbon radicals, said color former being capable of forming a dye taken from the group consisting of quinoneimine and azomethine dyes, light-sensitive silver halides, and a non-ionic wetting agent having a molecular weight of at least 400, and a plurality of oxyalkylene groups in a chain of atoms, said agent being free from sulfonic and carboxylic acid and quaternary nitrogen salt groups.

4. A photographic element hearing at least one gelatin layer containing a color former containing as an active color-coupling group a structure of the formula x t=t t=ta where X is a member of the group consisting of OH and NHR, where'R is a member of the group consisting of H and aliphatic hydrocarbon radicals, said color former being capable of forming a dye taken from the group consisting of quinoneimine and azomethine dyes, light-sen- '6 sitive silver? halides, and' .a "non-ionic wetting agent having a molecular weight of at least 400, and a plurality of oxyalkylene groups in a chain of atoms, said agent being free from sulfonic and carboxylic acid and quaternary nitrogen salt groups.

5. A photographic element bearing a light sensitive silver halide stratum I and at least one water-permeable colloid layer containing a color former containing as an active color-coupling group'astructure of the formula J where X is a member of the group consisting of OH and NHR, where R is a member of the group consisting of H and aliphatic hydrocarbon radicals, said color former being capable of forming a dye taken from the group consisting of quinoneimine and azomethine dyes, a non-ionic wetting agent having a molecular weight of at least 400, and a plurality of oxyalkylene groups in a chain of atoms, said agent being free from sulionic and carboxylic acid and quaternary nitrogen salt groups, and a hydrotropic wetting agent.

6. The process of reducing color stain which comprises developing a photographic element containing a color former containing as an active color-coupling group a structure of the formula Magma where X is a member of the group consisting of OH and NHR, where R is a member of the group consisting of H and aliphatic hydrocarbon radicals, said color former being capable of forming a dye taken from the group consisting of quinoneimine and azomethine dyes and a silver halide image in the presence of a non-ionic wetting agent having a molecular weight of at least 400, and a plurality of oxyalkylene groups in a chain of atoms, said agent being free from sulfonic and carboxylic acid and quaternary nitrogen salt groups and removing the silver and silver salts.

7. A photographic element bearing at least one water-permeable colloid layer containing a color former containing as an active color-coupling group a structure of the formula where X is a member of the group consisting of OH and NI-IR, where R is a member of the group consisting of H and aliphatic hydrocarbon radicals, said color former being capable of forming a dye taken from the group consisting of quinoneimine and azomethine dyes, light-sensitive silver halides, and from 0.1 to 2.0 grams per liter of emulsion of a polyethylene glycol containing from '7 to 200 CH2CH2O- groups,

8. A photographic element bearing at least one gelatin layer containing 4,4-methylene-bis-(lphenyl-3-methyl-5-pyrazolone), light-sensitive silver halides, and from 0.1 to 2.0 grams per liter of emulsion of a mannitan monolaurite containing 2 to 3 polyoxyethylene chains of at least 8 carbon atoms.

9. A photographic element bearing at least one gelatin layer containing 4,4bis-(l-naphthyl-2- sulfamido phenyl) ether, light-sensitive silver halides, and from 0.1 to 2.0 grams per liter of emulsion of a mannitan monolaurite containing mmm 7 '8 2th 3po1yoxyethy1ene chains bf at-leasw cal-bun Number. Name Date atoms. 2,240,472 Swan Apr. 29, 1941 ANDREW BRADSHAW JENNINGS; 2,304,940." Mannes et a1. Dec. 15, 1942 OTIS WILLARD MURRAY. 2,322,027 Jelley et a1 June 15, 1943 5 2,324,831 Frohlich et a1. July 20, 1943 REFERENCES CITED "2,353,262 Peterson 61; a1. July 11, 1944 The following references are of record in the 2360390 1944 m of t patent: 2,423,549 Blake et a1. July 8-, 1947 UNITED STATES PATENTS FOREIGN PATENTS Nu b r N H I 4 Number Country Date 2,186,717 Eggert et a1. Jan. 9, 1940 442.522 Great B i ain Feb. 3. 1 6 

1. A PHOTOGRAPHIC ELEMENT BEARING A LIGHT SENSITIVE SILVER HALIE STRATUM AND AT LEAST ONE WATERPERMEABLE COLLOID LAYER CONTAINING A COLOR FORMER CONTAINING AS AN ACTIVE COLOR-COUPLING GROUP A STRUCTURE OF THE FORMULA 